Whatever you do, make it idiot-proof. Not because your drivers are idiots, but because the fewer precision maneuvers they have to do, the more awesome driving (and scoring!) they have time to do. - Ian Curtis [more]

Well my teams shop hasn't been nice to out past robots or even out new ones by drilling metal right over victors. Well as you may guess there is several pieces of tiny metal and a lot of dust in some that have me worried to even power them up for a fear of burning the up. So how to clean them?
theses 40 or so victors have all past their warranty age so opening isn't a problem but i notice this clear looking glue over the boards that have the metal fragments scattered near exposed connections.
I been think of putting them into a ultra sonic alcohol bath to clean them up but fear the wire bonds in the ICs would break. So how would you clean them besides a ear cleaner and some alcohol with a good amount of chair time.

__________________

I refuse to go silently into the night by taking the easy way out.
The manual doesn't have all the answers since nobody can plan for everything.
Things can be more simple than you think.

OK, let's be real clear about this - compressed air is one of the worst possible solutions for cleaning chips away from anything. This is particularly true when you are talking about electronics.

Go visit any high-quality precision toolroom or instrument shop, and you will probably find that this is a completely prohibited practice. The reason is pretty straightforward when you think about it. When you blow the chips away, they have to go somewhere. With a big blast of compressed air, you have no control over where the chips fly. They may be blasted out of the area of interest, but it is just as likely that some of them will be driven even deeper into tiny crevices or components where they will cause endless problems. I once helped tear down a medium-size lathe that had been used in a small shop for about two years where they constantly used the "blow all the chips away" approach. We found an entire handfull of chips and swarf that had been driven from the area around the headstock through the seals and into the gearbox and transmission of the lathe. It was not a pretty sight. It was not hard to imagine the effect that would have had on a electronic circuit board subjected to the same treatment.

If you want to clean chips away from electronics (or any other area), the correct solution is the exact opposite: vacuum. Use a shop vac with a small nozzle to suck away any metal fragments. If necessary, a judiciously applied cotton swab can be used to dislodge an embedded chip and free it to be sucked up.

-dave

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__________________ "I know what you're thinking, punk," hissed Wordy Harry to his new editor, "you're thinking, 'Did he use six superfluous adjectives or only five?' - and to tell the truth, I forgot myself in all this excitement; but being as this is English, the most powerful language in the world, whose subtle nuances will blow your head clean off, you've got to ask yourself one question: 'Do I feel loquacious?' - well do you, punk?"
- Stuart Vasepuru, 2006 Bulwer-Lytton Fiction Contest

If you want to clean chips away from electronics (or any other area), the correct solution is the exact opposite: vacuum. Use a shop vac with a small nozzle to suck away any metal fragments. If necessary, a judiciously applied cotton swab can be used to dislodge an embedded chip and free it to be sucked up.

-dave

.

agreed, one of our electrical engineers suggested this. we used compressed air to sweep the stuff on our floor to one side.

That's how we keep the F-18 FO (Foreign Object) free at Northrop Grumann. Workers drilling on the fuselage will either be holding an air powered vacuum next to the hole, or their buddy will, and we drill thousands of holes per shipset. Chips in the wrong place can just ruin a pilot's day.

ChrisH

Riddle: What is an F-18?

Answer: 100,000 rivets flying in formation

Quote:

Originally Posted by dlavery

OK, let's be real clear about this - compressed air is one of the worst possible solutions for cleaning chips away from anything. This is particularly true when you are talking about electronics.

Go visit any high-quality precision toolroom or instrument shop, and you will probably find that this is a completely prohibited practice. The reason is pretty straightforward when you think about it. When you blow the chips away, they have to go somewhere. With a big blast of compressed air, you have no control over where the chips fly. They may be blasted out of the area of interest, but it is just as likely that some of them will be driven even deeper into tiny crevices or components where they will cause endless problems. I once helped tear down a medium-size lathe that had been used in a small shop for about two years where they constantly used the "blow all the chips away" approach. We found an entire handfull of chips and swarf that had been driven from the area around the headstock through the seals and into the gearbox and transmission of the lathe. It was not a pretty sight. It was not hard to imagine the effect that would have had on a electronic circuit board subjected to the same treatment.

If you want to clean chips away from electronics (or any other area), the correct solution is the exact opposite: vacuum. Use a shop vac with a small nozzle to suck away any metal fragments. If necessary, a judiciously applied cotton swab can be used to dislodge an embedded chip and free it to be sucked up.

theses 40 or so victors have all past their warranty age so opening isn't a problem but i notice this clear looking glue over the boards that have the metal fragments scattered near exposed connections.

I am guessing you have already removed the bottom cover and that is where you are seeing this clear glue. That is what holds the circuit board in place in the top cover. An expert would remove this glue with a razor blade or scalpel and then lift the circuit board out of the case before using a good vacuum to remove foreign objects on both sides of the board. Since this is something you likely wouldn't want to tackle I will suggest that you first remove the fan assy. then invert the Victor so that the top is down. Tap the case with your fingers to try and loosen any material which will fall into the top of the case. Then while still inverted apply the vacuum to all openings in the case, around the transistors, etc. Remember the vacuum does nothing if air can't flow around the components and into the vacuum. Repeat this procedure at least once, tap and vacuum. Then do the same procedure on the bottom. I think you will find that a fine dust may remain on either or both sides of the board. For this a swab dipped in alcohol is best, if you change swabs often. You can pull on the cotton end to elongate it and make it fit into tight places as needed. Now inspect both top and bottom with a bright light and magnifier. When you are satisfied it's clean, reassemble and test.
Most of the circuit board has a conformal coating to keep out moisture so the most vulnerable spots are around the MOSFET transistor pins. Check these areas very carefully. With practice you will get the hang of tapping and vacuum.

__________________
Good Luck All. Learn something new, everyday!
Al
WB9UVJwww.wildstang.org
________________________
Robot is bagged, checkoff item 1 on the list. Now to practice. What are we recycling again?

Note that circuit boards like those in a Victor are water-resistant and can be cleaned in distilled water with no harm. Remove all of the plastic housing (and fan) and use a squirter bottle (like the kind athletes use for gatorade) to wash the board. A soft brush (like a kid's paintbrush) can be used to loosen dirt. Rinse again with distilled water, dry with paper towels and Q-tips (focus on the connectors and under components) and put it into a warm (150-200F, no more) oven to dry for an hour.

Some may be horrified at this suggestion - and they'd be right for certain types of components (like speakers and non-sealed switches), but Victors are OK for water contact - the one switch is sealed, and no other components are water-sensitive. The 'clear glue' coating the whole circuit board is the comformal coating that Al refers to.

Oh, be sure to use distilled water and not deionized water - any mineral residue left behind has the possibility of causing problems. And (duh!) don't power it up until it is dry - and even then leave it out for a day or three to make triple sure.

Rinse again with distilled water, dry with paper towels and Q-tips (focus on the connectors and under components) and put it into a warm (150-200F, no more) oven to dry for an hour.

Don

If you choose this method, you can use your kitchen oven set at the lowest temperature possible. Crumple up some aluminum foil to hold the component above the oven rack. (only small bits of the aluminum will be in contact with the component so that the rack doesn't melt into the plastic housing) Leave the oven door cracked open while the component is inside. Most oven doors have a detent to keep the door open a few inches. Above all, don't go take a nap! Watch the piece frequently during the drying period. I leave the piece inside the oven and then turn it off. That way the cool down cycle is very slow. You can nap during this part. This technique has worked well for electronics dropped into lakes and rivers and toilets or left out in the rain. It may not fix a multielement lens with water between the elements but I have revived several cameras dropped into sinks at concerts or left on the top of a car during a rainstorm.

__________________
Good Luck All. Learn something new, everyday!
Al
WB9UVJwww.wildstang.org
________________________
Robot is bagged, checkoff item 1 on the list. Now to practice. What are we recycling again?

Ah, at that point there shouldn't be any plastic housing, it having been removed to get to the circuit board.

Victors come apart easily, pry off the bottom cover and the rest comes out with a gentle push from above.

The foil idea isn't bad, though, since the rack can get a bit too warm sometimes. I just set the over to the lowest temp, wait 15 minutes for it to warm up, turn it off and pop the boards into the over to dry (I do this for several different kinds of electronics) and can then ignore it for 2-3 hours. (Remember to take it out, though, before someone decides to preheat the oven for leftover pizza!)

Just remember, static builds up on dry surfaces, so discharge your charge on something metal before touching the board.

Note that circuit boards like those in a Victor are water-resistant and can be cleaned in distilled water with no harm.

They were designed that way so they would be compatible with the water-based ga.... oops, sorry, we aren't supposed to say anything about that. Never mind.

-dave

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__________________ "I know what you're thinking, punk," hissed Wordy Harry to his new editor, "you're thinking, 'Did he use six superfluous adjectives or only five?' - and to tell the truth, I forgot myself in all this excitement; but being as this is English, the most powerful language in the world, whose subtle nuances will blow your head clean off, you've got to ask yourself one question: 'Do I feel loquacious?' - well do you, punk?"
- Stuart Vasepuru, 2006 Bulwer-Lytton Fiction Contest